Texas Local Government Code - LOC GOV'T § 83.009. Assistant Treasurer or Treasury Deputy

(a) The appointment of an assistant treasurer or treasury deputy must be in writing, be signed by the county treasurer, and bear the seal of the county court.

(b) A person appointed as an assistant treasurer or treasury deputy, before beginning to perform the duties of office, must take and subscribe the official oath, which, together with the certificate of the officer administering the oath, must be endorsed on the appointment. The appointment and oath shall be deposited and recorded in the county clerk's office.

(c) An assistant treasurer or treasury deputy acts in the name of the county treasurer as directed by the county treasurer and may perform all official acts that the county treasurer may perform at the discretion of the county treasurer.